Summary of Week 11: 14 – 21 March First week of intensity ramp up Gianluigi Arduini and Jan Uythoven for the LHC teams Aim of the week: Physics with 100 + bunches, Luminosity > 1e32 136 bunches ! 21/03/2011 LHC 8:30 meeting

136 bunches: Lumi lifetimes: GOOD Sunday 20/03 05:50 Dump fill #1639 Cryo lost S18 matching section. Temperature oscillation in QRL line C affecting DFB MB. Second fill of 64 bunches after 7 hours in coast 09:22 Cryo recovered – access CMS 10:15 Injecting for physics 11:40 Stable beams 64 bunches – 3rd fill 18:00 Dump 21:30 Stable beams 136 bunches – 1st fill 06:00 Operator dump RB S12 and S23 tripped during ramp up, active filter 136 bunches: Lumi lifetimes: GOOD 21/03/2011 LHC 9:00 meeting

Injecting pilot + trains of 8 + trains of 24 Great job from the injector shift crews who changed settings from 8 to 24 bunches (75 ns) in 5 minutes! But bunches could be a bit more equal… BPMS IP6 Interlock test 24b 8b 21/03/2011 LHC 8:30 meeting

Vacuum Experimental Areas 136 bunches ATLAS had vacuum spikes at about 21:00... until 21:15 it went up by a couple of orders of magnitude, by now recovered 10%. 1e-6 mbar !!! M.Jimenez 21/03/2011 LHC 8:30 meeting

136 bunches - Vacuum activity starting Vacuum around the injection kickers MKI IP2 and IP8 136 bunches IP2 – Kicker tank changed 64 bunches IP8 – not opened 21/03/2011

Vacuum at the IPs during fill o-night 21/03/2011 LHC 8:30 meeting

Timing Distribution problem Overview of the week 160 x 1030 cm-2s-1 Lumi’s 2e13 DC BCTs Inj. tests 48 b 32 b 64 b 136 b Skip 8 b Stable Beams: 3b Timing Distribution problem Tot. L = 8.7 pb-1 MPS tests 21/03/2011 LHC 8:30 meeting

Fills of the week Tot. L = 8.7 pb-1 1634 32 1.18/1.12 30 2.8 0.51 # bun ches Average bunch population@coll [1011 p] Initial luminosity [1030 cm-2s-1] eHV @coll (from init. Lumi) Integrated luminosity [pb-1] Coast duration [hours] Turn-around to next fill 1634 32 1.18/1.12 30 2.8 0.51 06:00 02:25 1635 1.18/1.17 33 2.7 0.009 00:06 05:00 (RF) 1636 1.16/1.15 0.56 02:41 1637 64 1.18/1.15 66 1.3 06:40 02:45 (Inj) 1638 1.14/1.14 2.6 1.34 07:05 05:50 (CRYO) 1639 65 1.21 06:20 02:30 (MPS) 1640 136 1.18/1.18 148 3.7 08:30 Tot. L = 8.7 pb-1 21/03/2011 LHC 8:30 meeting

rMPP ok for every intensity step Check list filled in for each step On edms 21/03/2011 LHC 8:30 meeting

What kept us busy during the week Test ramp with 8 bunches Aim: validation ramp and squeeze with 75 ns beam and transverse feedback ON through the squeeze Larger oscillations observed on B2 H tune corrections – tune feedback locking on mains harmonics leading to QPS trigger on RQTF.A23B2 and RQTF.A34B2 8 bunches 21/03/2011 LHC 8:30 meeting

Test ramp with 8 bunches Mains harmonics, not side bands Reduced gain of the transverse feedback all through the ramp Easier with 32+ bunches ! 100 Hz 21/03/2011 LHC 8:30 meeting

Wednesday Evening Problem with the timing distribution RQTD.A12B2 and RQTD.A67B2 tripped off due to large trim request – still not completely understood Resulting dump was proper, but badly timestamped Post Mortem and XPOC data New release of the MTG firmware failed Took 36 h to convince that MPS is ok to continue 32 b Mean time 1.38 TeV prep. FIDEL, decay comp. at injection Validation tests Jump in Time 21/03/2011 LHC 8:30 meeting

Continue the intensity increase: RF dump on Friday night Following a modification introduced during the Xmas stop, the RF FGCs crash if they receive 3 or more simultaneous timing events (as in the case of the automatic optimization of all the IPs) The bug has been identified and fixed by Q. King – new firmware version to be released at the next best occasion. This explain why the problem occurred when using the application to optimize the separation simultaneously at all IPs For the moment we do not to use the 'optimize all' option in the luminosity scan application! Continue the intensity increase: 136 bunches = 8.5 MJ/beam 21/03/2011 LHC 8:30 meeting

Plans Coordinators this week R.Assmann, M.Lamont Recover RB trip Next: fill another 136 bunches This week (possible program) Increasing to 200 bunches 1.38 TeV run Injection studies, prepare scrubbing 21/03/2011 LHC 8:30 meeting

Outstanding Injection of 96 bunches Timing distribution FGC firmware update Collimation system controls fix 1.38 TeV setting-up Crossing angle all zero: OK TCTs to set up & loss maps Interlock tests for the roman pot RF voltage limit interlock Longitudinal blow-up Wire scanners Abort gap cleaning Injection gap cleaning 21/03/2011 LHC 8:30 meeting

Timing Distribution problem Overview of the week 160 x 1030 cm-2s-1 Lumi’s 2e13 DC BCTs Inj. tests 48 b 32 b 64 b 136 b Skip 8 b Stable Beams: 3b Timing Distribution problem Tot. L = 8.7 pb-1 MPS tests 21/03/2011 LHC 8:30 meeting